- 著者
- Sawaki D. Kobayashi W. Moritomo Y. Terasaki I.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.98, no.8, pp.081915, 2011-02
- 被引用文献数
- 104 26
We investigate thermal rectification in a bulk material with a pyramid shape to elucidate shape dependence of the thermal rectification, and find that rectifying coefficient R is 1.35 for this shape, which is smaller than R = 1.43 for a rectangular shape. This result is fully duplicated by our numerical calculation based on Fourier’s law. We also apply this calculation to a given shape, and show a possible way to increase R depending on the shape.
- 著者
- Moritomo Y. Nakada F. Kurihara Y.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.11, pp.111914, 2009-03
- 被引用文献数
- 5 4
Electrochromism is extensively investigated for practical application of display and memory devices. To develop the material, reliable information on the optical and electronic properties of the solid film is indispensable. Here, we propose valence-differential spectroscopy that can selectively extract the spectral components related to the oxidized/reduced metal site. We applied the spectroscopy to Co2+–Fe2+delta and Co2+delta–Fe2+ cyanide films with finely control of averaged valence (delta) of the transition metal by external electric pulses. The spectroscopy revealed transition energy E, width Gamma, and oscillator strength f of the spectral components related to the transition metal.
- 著者
- Moritomo Y. Nakada F. Kamioka H. Kim J. E. Takata M.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.14, pp.141907, 2008-04
- 被引用文献数
- 4 4
The guest-host interaction is one of the promising tools to control the material state. Here, we found that a cyano-bridged compound Na0.50Co[Fe(CN)6]0.723.8H2O shows a first-order structural phase transition below a critical pressure Pc (150 Pa) at 300 K. Judging from suppression of the OH stretching mode in the infrared spectra, we ascribed the phase transition to desorption of the ligand waters. The phase transition accompanies a significant change of the visible absorption spectra, reflecting the strong hybridization between the Co eg state and the CNσ states.
1 0 0 0 OA On-off optical switching of the magnetic and structural properties in a spin-crossover complex
- 著者
- Kato K. Takata M. Moritomo Y. Nakamoto A. Kojima N.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.90, no.20, pp.201902, 2007
- 被引用文献数
- 25
A photoexcitation is one of the promising external fields to control the material phases. Here, the authors have demonstrated that the magnetic and structural properties of a spin-crossover complex, Fe(phen)2(NCS)2 (phen=1,10-phenanthroline), can be reversibly switched by the on-off action of the continuous photoexcitation at the same temperature. The structural data suggest that the density of the high-spin Fe2+ in the photoinduced phase is about 0.88. Suppressed atomic vibrations of the photoinduced phase exclude the conventional heating effect as the origin for the observed optical switching.